package com.heima.service;

import com.heima.mapper.UserMapper;
import com.heima.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class UserService
{
    @Autowired(required=false)
   private UserMapper userMapper;

    public User queryById(Long id)
    {
        return userMapper.selectByPrimaryKey(id);
    }
}
